[Haskell-beginners] confused by <-

Chaddaï Fouché chaddai.fouche at gmail.com
Thu Sep 27 21:43:35 CEST 2012


On Thu, Sep 27, 2012 at 9:25 PM, Chaddaï Fouché
<chaddai.fouche at gmail.com> wrote:
>
> >    body <- try (simpleHttp "http://www.google.com")
> >    case body of
> >        Left (SomeException _) -> jsonToRepJson $ object ["response" .= ( show "ERROR: NO DATA FOR ONE REASON OR ANOTHER")]
>
> I think that should work...
>

Since the signature was made necessary by the ambiguity on which type
of exception you wished to catch with your "try", using (SomeException
_) in your pattern match should make that clear. By the way, why are
you show()ing a String ? The only thing that does is adding quotes
around it and escaping some characters, shouldn't you just use :

>        Left (SomeException _) -> jsonToRepJson $ object ["response" .= "ERROR: NO DATA FOR ONE REASON OR ANOTHER"]

-- 
Jedaï



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